Meningeal hemangiopericytoma: histopathological features, treatment, and long-term follow-up of 44 cases.

Forty-four cases of meningeal hemangiopericytoma that were treated between 1938 and 1987 are reviewed. Fifty-five percent of these tumors occurred in men. The average age of the patients at diagnosis was 42 years. The average duration of preoperative symptoms was 11 months. Symptoms were related to tumor location, which was similar to that of meningioma. The operative mortality was 9% overall, and has been zero since 1974 (18 patients). The average time before the first recurrence was 47 months, with the recurrence rates at 1, 5, and 10 years after surgery being 15, 65, and 76%, respectively. Ten patients have developed extraneural metastasis, mostly to lung and bone, at an average of 99 months after the first operation. The 10- and 15-year rates of metastasis were 33 and 64%, respectively. The average survival period has been 84 months, with survival rates at 5, 10, and 15 years after surgery of 67, 40, and 23%, respectively. The histological diagnosis of the tumor was not related to survival or recurrence and did not change with recurrence. Tentorial and posterior fossa tumors tended to be more lethal. Total tumor resection favorably affected recurrence and survival, as opposed to subtotal resection. Metastasis adversely affected survival, and was followed by death at an average of 24 months after its diagnosis. Radiation therapy after the first operation extended the average time before first recurrence from 34 to 75 months, and extended survival from 62 to 92 months.